Energy efficiency assessments in designSeminal decisions and effective processesMarc Allen – Principal Consultant

Contents• Traditional design processes

• What is your energy (and carbon) liability?

• Energy efficiency design reviews

• Case study

“Energy savings of 25 to 37 EJ per year are available based on proven technologies and best practices.”

IEA - 2007

Traditional design process

Traditional design process

Scoping studyLab tests Prefeasibility study

Feasibility studyDefinitive feasibility study

Bankable feasibility study

Front end engineering

designDetailed design

Design decisions

made here

Lots of data available

Traditional design process80% of the major design decisions are made within the first 20% of work

Processing route chosen

Major equipment selected

Data available during later design to make decisions on energy efficiency

Changes at this point are very expensive

Conduct energy efficiency assessments as early as possible

Update your financial model

Creating a financial caseProject will have a financial model

How are energy costs treated?

Starting price inflated over time?

Realistic price forecast based on assumptions?

Energy price forecastingEscalating a current price with inflation will generally understate future energy costs

Inflation in Australia has increased 2-5% p.a. on average

Oil prices have escalated at ~35% p.a. since 1999

• Reality takes into account supply/demand factors

WA natural gas priceRegional variations need to be accounted for

World natural gas prices have decreased since 2008

Prices in WA have increased though and are expected to increase further

Carbon pricingClean energy future policy very likely to be implemented

$23/t carbon price will be included as of 1 July 2012

Price will be escalated by 2.5% p.a. Before moving to a market based mechanism

Facilities with (non diesel) direct emissions in excess of 25 kt/a will have a permit liability

What does $23/t CO2-e add to commodity prices?

Gas$1.20/GJ

Total $13.20/GJ

Electricity$20/MWh

Total$120/MWh

Black Coal$60/t Total$175/t

10%

20%

30%

Petrol$0.06/LTotal

$1.46/L

Diesel$0.06/LTotal

$1.56/L

3%3%

Energy efficiency design reviews

Carbon and energy baselineEnergy cost increases are likely to be significant

Carbon will represent an additional cost

Important to define your energy and carbon footprint as early as possible

Include in the financial model – sensitivity analysis

Energy efficiency design reviewsCheaper to make big decisions during the early stages of design:

•In pit crush and convey vs haul

•HPGR vs traditional milling

•Hydromet vs pyromet

•Atmospheric vs pressure leach

•Heat recovery systems

•Pinch analysis

Financial model fully defined

Conduct energy efficiency design reviews

The earlier the better!

Other opportunitiesControl system changes

• Conveyor shutdowns

• Soft starters

• Telemetry on underground ventilation

• Expert systems on grinding circuits, EW

Minor equipment

• VSDs on pumps, compressors, ventilation

• Optimisation of pipe runs to minimise losses and pumping requirements

Carbon reduction projectsAlternative neutralisation reagents or processes

Fuel switching

Power station design

Renewable energy projects (include RECS in financial model)

Case studyEnergy efficiency design review completed for a coal project in Queensland

PFS had been completed at time of design review

Design review completed in a workshop environment with key stakeholders from the entire operation

Just do it Strategic

Symbolic Leave Behind

High cost

High impact

Low impact

Low cost

Case studyOperation split into the following areas:

Management and Systems – 4 projects identified

Infrastructure – 8 projects

Layout – 4 projects

Ancillaries – 2 projects

Supply – 1 project

Technology – 6 projects

25 projects identified in total3 were in “Leave Behind” category

ConclusionsEnsure energy costs are predicted as accurately as possible

Conduct energy efficiency design reviews as soon as you can

Save money in the long run